Meanwhile, in Maine ...

7/11/12 2:15 PM EDT

Former Maine Gov. Angus King, meanwhile, holds a substantial lead over his Republican and Democratic rivals in the race for Maine's open U.S. Senate seat.

Fifty-five percent of those polled said they support King, more than double the support for the closest candidate, Republican Charlie Summers. Twenty-seven percent of respondents said they favor Summers and 7 percent said they favor Democrat Cynthia Dill.

King, running as an independent, is drawing support from members of both parties, especially Democrats. Sixty-seven percent of the Democrats polled said they support King, while 17 percent said they support Dill, the party's nominee.

King could theoretically control the balance of power in the Senate after November and has refused to indicate in any clear way which party he's more likely to caucus with. He told potential donors during an event in D.C. last month that they shouldn't give to his campaign if they needed a signal on partisan affiliation.